hi! i too am dealing with ich right now in my reef. I treat with garlic extreme twice a day, directly into the tank, and turne doff my skimmer. I don't have a heater to raise temp, and since I'm the paranoid type, am also using a combination of methinadazole and focus. The meth is for internal and external parasite, the focus is just to make sure the medicine gets taken in and assimilated by the fish. The powders get mixed with some semi-melted frozen food (they have to be ingested, don't dump it willy nilly in the tank) which I then refreeze and break off in little clumps. I also put some garlic on the food too, which helps stimulate appetite. I've seen the spots go away and come back more than once, and my poor gramma is beating his head against rocks and gravel trying to shake the cysts. Doesn't look like my goby or cardinal are adversely affected, and all of my corals and inverts (shrimp, hermits, porcelain crab, snails) are totally fine. Been treating for over a week.
I've been in contact with Seachem, who makes the meds (i love seachem, btw, they always reply quickly are are very helpful), and between them and other posts have found it can take over 4 weeks to eradicate. I'm on week two and hoping for the best. Good luck to both of us!
BTW, i love the Chevelle! one of my faves (I'm partial to the '70)